Uniform Circular Motion

Syllabus tag: KCSE | Physics | Form 4 | Topic 32 Uniform Circular Motion

Lesson objectives

By the end of this topic, you should be able to:

• Define angular velocity, period and frequency for circular motion.
• Relate linear and angular velocity.
• Explain centripetal force and acceleration and apply the formulae.
• Describe applications including the centrifuge, banked tracks and satellites.

Summary

In uniform circular motion the speed is constant but the velocity is not, since the direction changes continuously. The body therefore accelerates towards the centre, and this requires a centripetal force, F = mv² ÷ r. There is no outward force; the apparent one is inertia.